Seam-welding apparatus.



R. P. MILLER. 'SPAM WELDING APPARATUS.

APPLICATION FILED SEPT. 25, 1911.

1,031,812. y Patented July 9,1912.

Lave nfor- M Wfl/w @az/ R. F. NAILLER.

SRAM WELDING APPARATUS;

APPLIoA'rIoN FILED Smm-25, 1911.

1,031,812. v Patented July 9,1912.

2 SHEBTS-SHEET 2.

zontally in opposite free.y end. -Also extending laterally outward from the piston 10 direct-ly above and coextensive with the mandrel is a combined support and guideway 16 for a traveling-carriage which supports the hammer and combined hammer head and electric contact or terminal to be referred to presently. This support and guideway preferably consists of two parallel channels 16 arranged back to back or with their flanges extending horidirections.

The work to be welded is inserted' between the mandrel and sup ort 16, andaiter the work is inr place, tiiefree ends of these parts are designed to be fastened together bya link 17, and locking lever or handle 18. To insert the work onto the mandrel, the lever 18 is thrown upwardly so as to permit the link to be released and swung downwardly, and to lock the mandrel and support after the workis in posi` tion, the link is replaced and the lever 18 thrown downwardly. l 4

The mandrel 15 constitutes one of the terminals or cont-acts of the welding circuit,

and has one terminal conductor 19 of a low voltage high amperage circuit 20 connected thereto. To apply the welding heat locally to one part of the work at any instant and progressively along the seam, vI Lemploy a combined hammer head and electric terminal or contact 21, the lower end of the hammer head being arranged just above the mandrel and in the central plane therewith. This hammer head and terminal 21 `is provided with a laterally projecting arm 21 which is provided with cooling flanges 21b and has connected thereto the second terminal conductor 22 of the welding circuit 20.

In connection with the hammer head 21, 'I employ a maintain a substantially constant pressure on the hammer head during the welding op? eration and lthereby press the Loverlapping portions 'of the work down onto themandrel at the point o application of the current so as to secure'at all points of the seam as the hammer head is moved along the same, good contact between theparts o the work and between the worlr and electric terminals. The hammer is also designed to deliver, independently Aof the pressure above referred to, rapid hammer blows to the hammer head and thus to the work at the point of applicati-cnet the heating current. I preferably employ a pneumatic hammer,

u although other lforms of luid.l pressure. or

mechanical hammers might be employed.

In the construction shown, the hammerin-v cludes a cylinder 23which receives the upper reduced end of the hammer head and terminal 21 and delivers the desired pres-4 sure to the hammer head to obtain effective contact between the parts of thev work and the terminals. The hammer' blows are deuniform rate in spite of hammer 23 which is designed t0 livered to the end of the hammer head by a reciprocating piston 23". Surrounding the cylinder 23IL is a second cylinder or sleeve 23 containing ports and valve members which need not be described in detail. The air is admitted -at the port 23d and fluid pressure is exerted upon the piston-like member 23 which bears directly on the inner barrel .or cylinder 23", and which has a close tit port 16 and being supported midway between the two sides or parts 24 of the carriage which project above and beneath the channels of the trolley support and are provided with wheels 24 which engage both the upper and lower channel flanges., mechanism for shifting the carriage and consequently the hammer and hammer head, in the preferred embodiment of my invenvtion, includes an electric motor 25, which is supported at the inner end` of the trolley support and guideway 16, and a feed screw 25 which is connected by gearing 25h to the motor shaft, and between its ends has a working lit in a nut 25 carried by the hammer carriage or trolley,'as best disclosed in Fig. 3. With this mechanism, the hammer can be shifted lengthwise of the seam at a the heavy pressure with which the hammer head bears onto the work. l

To weld a seam between two plates or between t-he edges of a boiler or other tubular member, the edges are firsttemporarily asten'ed in position by pin-riveting or other suitable means and then the tubular member or other work is Aplaced on the mandrel in the manner previously stated. The heating current is then applied 'and simultaneously the motor 25 and hammer 23 are started in operation, thereby causing the assage of the heating current across the Joint so as t o heat substantially to plasticity the work dibeneath the hammer head, and at the same time causing the parts ofthe work to be rmly clamped together and in good electrical contact with the terminals so as to assistl in the heating action and in the contining of the current to the point beneath the hammer head, and causing simultaneously with the heating current and pressure, the delivery of the welding blows, the heating and welding action taking place gradually and at a uniform rate 'along tlie entire seam The ioo

current.

Having thus described my invention, what by the uniform travel ofthe hammer,ham mer head, and progressive application of overlapping parts of the work so as to cause substantially all the current to pass directly across the overlapping parts in line with the application of pressure, a hammer arranged to deliver rapid welding blows to the hammer head and terminal, and means for causthe seam.

ing a relativemovement between the work and the hammer and hammer head during the heating and welding action, so thatthe partsof the seam will be heated and welded gradually and progressively lengthwise of 2. In a lapvseam 'Welding apparatus, a pair of electrlc terminal members, one-being in the form of a fixed mandrel and t-he other in the form of'a hammer head, said mandrel and hammer-head being designed to cause the passage of a welding current acrossl the joint and to .transmit heavy pressure .tothe Work so as to cause substantially all the curi rent to pass directly across the overlapping parts of the work in line with the applica-- tion of pressure, a hammer arranged to deliver rapid welding blows to the hammer head so as to weld together the parts at the point of application of the heating current,

and means for causing during the heat-ing and welding action and at a uniform rate a welding will be secured progressively along relative movement between the work and the hammer head so that uniform heating and the seam.

3. In a lap seam welding apparatus, a mandrel adapted to support the work and constitute an electric terminal, avcombined hammer head and terminal adapted to transmit pressureto the work andtocause the passageof a heating current therethrough across the joint, a Ahammer having 'means for causing a substantially constantv pressure on the hammer head and for delivering rapid welding blows to the latter, and means for causingduring theA heating and welding action a relative movement between `the Work andthe hammer and hammer head lengthwise of `;;:.tl'1e seam so that the parts ofthe joint willbe' ...uniformly heated and welded progress in the direction of the seam.

4. In a'lap seam'welding apparatus a pair of electric termina-l members, one be" a inthe form of a fixed mandrel and the other in the form of a traveling hammer head, said mandrel and hammer, head being adapted to transmit pressure to the part' to be welded and to cause the passage of a welding current across the joint and to transmit suiiicient pressure onto the work to cause Substantially all of the current to pass through the overlapping parts of the work in line with the applicatlon of pressure, a' hammer arranged to deliver rapidwelding blows to the hammer head and thereby weld the seam at the point of application ofthe heating current, a carriage carryingfisaid hammer, a support and guideway for the carriage, and

Ameans for shifting the carria e, hammer,

and hammer head during the eating and -welding action along said" support so that the seam will be heated and welded progressively lengthwise thereof. 5. In a lap seam welding apparatus, a pair of electric terminal members, one bei in the' form of a'fixed mandrel adapted to support the work, and the other inthe form of a traveling' hammer head, said mandrel and hammer head being designed to transmit pressure to the parts'to be welded and to cause the passage of a welding current across the joint, a hammer having means for4 causing a substantially constant pressure to ybe applied to the hammer head and for delivering rapid welding blows to the latter, a l

support and guideway for the hammer, and means for gradually shifting the hammer andhammer head along the support lengthwise of the seam, whereby there 1s a' progressive heating and sea-m welding act1on. j 6. In a seam welding apparatus, a vertlcally movable support having secured theeto a laterally projecting mandrel and a Support and guideway for a hammer arranged abovethe mandrel, a carriage adapted to travel'along said support, a hammer carried by said carriag'eand having means for delivering a substantially constant heavy pressure and rapid welding blows to the work,

and a hammer head at the lower end'of the l hammer adjacent the-mandrel, said mandrel constituting one electric terminal and the hammer head constituting a second/electric terminal and being designed to transmit pressure to and tocause the passage of a heating current between the partsto be welded, and means for shifting the carriage and hammer along the support, so that the hammerI ismoved gradually along the seam during the heating and /welding action.

In testimony whereof, I hereunto aix my signature in the presence of twopwitnesses.

RAYMOND F. NAILLER. VVitnesses: I

R. SULLrvAN,

' A. F. Kwis. 

